"That plan will propose bringing those detainees to an appropriate, secure location in the United States," Carter said. "While we work with Congress on a way forward, we will continue to transfer Guantanamo detainees to other countries when and as we have mitigated the risk to the United States."
A senior administration official said the plan does not include naming a specific site for relocation but rather includes a list of potential locations.
The possibilities are understood to include the federal Supermax prison in Florence, Colorado; the military prison in Leavenworth, Kansas; and the Naval Consolidated Brig in Charleston, South Carolina.
The official said Obama is in the "final stages" of reviewing the plan.
It is unclear when the administration's proposal to bring detainees to the U.S. will be presented to Congress, but House Homeland Security Committee Chairman Michael McCaul, a Republican, is not waiting to blast it.
"What Commander in Chief would let the enemy go back to the battlefield in the middle of a war?" said McCaul in a statement Thursday. "Sadly, the President seems more focused on letting terrorists loose than on rounding them up."
And House Speaker Paul Ryan responded to Carters announcement that some detainees will be brought to the U.S. by saying in a statement, "There's only one problem with that, Mr. Secretary: It's illegal, and that's not going to change anytime soon."
Carter's announcement came as the population of the detention center dropped below 100.
The U.S. military transferred 10 more of the detainees from the prison on Wednesday, delivering them to the government of Oman.
That leaves 93 at the facility -- 34 of them already cleared for removal -- down from a peak in 2003 of 680.
Those who were removed this week include members of al Qaeda who fought U.S. forces in Afghanistan, including a member of Osama Bin Laden's security detail and five detainees who were deemed "high risk" to the U.S. and its allies after a 2008 review.
Obama says the prison -- which holds suspected members of terrorist groups captured overseas -- is a recruiting tool for terrorists and costly to maintain.
During his presidency, the number of detainees has dropped from 241 to 107. But the President has hit roadblock after roadblock -- most often placed by Republicans on Capitol Hill -- in his effort to clear out the prison, one of his key campaign promises and something he reiterated during his State of the Union address on Tuesday.
"The administration is working within the current statutory regime to make sure that owe can reduce that population," Attorney General Loretta Lynch said in an interview with CNN on Wednesday. "I believe the President looks forward to continuing the discussion with Congress on the best way to resolve the matter."